I would think the biggest concern is that you purchase from a reputable source to make sure you are receiving the product you think you are buying. IOW counterfeit products have been finding their way into the marketplace.

I don't agree with annz. I bought Frontline from a pet store and it turned out to be counterfeit. My dogs went through a terrible time with fleas multiplying like mad. I took them to the vet and she was appalled and wanted to know if I'd gotten it from them. I told her where I got it and she said if I had gotten it from them and had a problem, they could have exchanged the product and looked into the problem. I would never buy from a pet store again. It isn't worth it!!!

I got some from the internet, referred from a TV ad and it worked just as well as the vet's. Cat is indoor so I gave the extras away as according to the vet, the fleas will jump the cat and die and eventually there will be no more to infest the cat unless you have visiting outdoor pets. Credit card purchases also offer some protection against counterfeits if you can report the problem right away.

Cindy, Your information is incorrect. A prescription is not required for Frontline Plus. Many reputable online suppliers sell it, and it's completely legal to do so as it's an over the counter medication. Vets stock Flea products as a convenience to their customers and for profit. Frontline Plus is typically NOT sold in pet stores, and that is likely the manufacturer's marketing decision.

To the original poster's question: Frontline Plus sold by a vet should be exactly the same as Frontline Plus purchased from any reliable vendor. Some good vendors are Entirely Pets, Omaha Vaccine, Foster and Smith. There are others.

Cynthia, I stand corrected. I checked Frontline's website. It did use to be prescription only, but is not now. Heck, I may be a convert if I can get it cheaper. Three 100 lb dogs are not cheap on the frontline front.

Why are FRONTLINE Brand Products only available through my veterinarian?
It is Merial's sales policy to sell our small animal products only where a veterinarian/client/patient relationship exists. Merial believes that the veterinarian is the only professional qualified to serve the health care needs of pets, the concerns of their owners and the appropriate use of our small animal products such as FRONTLINE Brand Products.

For smaller dogs, it's cheaper to use a larger dosage and split it.
I do this with my two 20 poundish dogs. Use one package, make a line on it with a sharpie and have dh hold the dogs while it's applied.